Centrifugal switch



JanQ Z S, 1941. G. s. MOORE ETAL CENTRIFUGA'L swI TcH" Y Original Filed Feb. 21, 1938 2 Sheets-Sheet 1 s. s. MOORE ETAL 21,701

CENTRIFUG'AL SWITCH Original Filed Feb. 21. 1938 2 Sheets-Shet 2 Reissued Jan. 28, 1941 Re,

UNITED STATES PATENT OFFICE 21,701 CENTRIFUGAL SWITCH Giles S. Moore and Elmer G. Streckfuss, Indianapolis, Ind., assignors to G. B. M. Electric Company, Inc., Indianapolis, Ind., a corporation of Indiana Original No. 2,128,841, dated August 30, 1938, Serial No. 191,784, February 21, 1938. Applica- $50119 for reissue August 30, 1940, Serial No.

10 Claims. (Cl. 200-80) This invention relates to electrical switches their edges only are wiped by the common conbroadly and is particularly concerned with ductor brush, thereby permitting a secure and switches of the governor-controlled type gencompact unit in which any chance of sticking or erally used with signal and like circuits wherein bending during service is eliminated and insuring a plurality of signals, such as lights or audible maximum life to the switch unit in general. 5 sounding devices, are adapted to be electrically Further objects are: to generally improve energized in successive order, such for example and render more durable switch units of the mulas the electric speedometer-odometer-signal systiple contact type, to provide a switch unit which tem disclosed in the copending application of may be manufactured in volume and at a rela- Giles S. Moore, Serial No. 190,492 filed February tively low cost, and to generally simplify and ren- 10 14, 1938. der more durable switches of this type.

Commercial production of the foregoing type The foregoing and other objects and advanof switch units involve problems which are not tages will become apparent in view of the folapparent in experimental units. Each group of lowing description taken in conjunction with the signals generally calls for a differently timed drawings, wherein: 15 switch, and since certain tolerances must be Fig. l is a phantom view in sectional side elemade for governor springs, the contact bank vation of the front portion of a motor vehicle, must also be adjusted to compensate for certain illustrating the improved switch operatively invariations in strength of the spring. Hence, if stalled in conjunction with an electric speedomgo accuracy is to be maintained, the switch bank eter-odometer-signal unit; must be set or timed not only in accordance with Fig. 2 is a transverse sectional view taken the stepped signals but also in accordance with through the drivers compartment of Fig. 1; variation in the governor action of the respective Fig. 3 is a plan view of the improved goverunits. nor-switch assembly with the top of cover plate An important object of the present invention, of the housing or switch box removed; .25 therefore, is to provide a switch of the stepped- Fig. 3 is a detail perspective view of the con signal, governor-controlled type embodying a tact edge portions of the switch plates forming bank of contacts so constructed as to be readily part of the switch assembly;

adjustable to time the switch in accordance with Fig. 4 is a view in section and end elevation 0 the signals with which it may be associated and taken substantially on the line 4-4, Fig. 3; and also to compensate for variation in the actu- Fig. 5 is a wiring diagram for the signal circuit 'ating parts of the switch. of Figs. 1 and 2 with the improved switch incor- Another object of the invention is to provide porated therein. a switch unit of the type specified having a Figs. 1 and 2 illustrate a signal system for ve- 5 multiple of contacts arranged to be contacted in hicles of that type wherein a bank of signal successive order by a movable switch member, lights indicating stepped mileages are mounted such as a common conductor brush, the said conexteriorly of the vehicle, and another bank, tacts being unusually compact and permanently namely, a speedometer bank, are mounted on braced against displacement due to shocks and the interior of the vehicle to indicate a speed of 0 jars incident to the travel of the vehicle or other travel of the latter. The system illustrated also objects to which the signal system may be apincludes diagrammatically an electrically driven plied. odometer. These units call for a switch of the Another object of the invention is to provide a multiple contact type having a multiple switch switch of the multiple contact, governor-ccnmember adapted to'wipe the contacts in direct trolled type having a movable switch arm carrelation to the speed of travel of the vehicle. 45 rying a brush which is energized from a relatively In Figs. 1 and 2, the vehicle is generally indistationary member to which the common concated at A and may be powered by the convenductor is connected, thereby eliminating the ne tional internal combustion engine at dotted outcessity of insulating the governor actuated switch line which is indicated at M. A speedometer is arm and permitting use of metal parts at points generally indicated at 5 and embodies a series where a bearing action takes place. of lights 5a, 5b, 5c, 5d, 56 and '51. On the top of Another object of the invention is to provide the vehicle is .a bank of signal lights generally a multiple contact, governor-controlled switch indicated at I and embodying a plurality of lights wherein the respective contacts which make up 1a, 1b, 1c, 1d and 1c. The speedometer casing a the bank consist of flat segments so arranged that is mounted on the conventional pane1 board 6.

or less in detail in Figs. 3 and 4.

Referring now to Figs. 3 and 4, ,a governor shaft 9 is mounted in bearings Ill and I 00. installed at opposite ends of the switch. box or housing 8, said shaft being suitably connected to the drive shaft of the motor vehicle, not shown,

Mounted on the shaft 9 is av synchronizing governor comprising a plurality of Weights I311, I31) and I36, each of which sleeve 16 having an annular groove ll formed therein, the sleeve being mounted to slide longitudinally on the said shaft 9. Between the anchor member or collar l5 and the sleeve I5 is a governor spring l8.

The operation of governors of this general type is well understood in the art. As the shaft 9 revolves, the weights are caused to swing outwardly due to centrifugal force, the sliding sleeve l6 moving inwardly against the resistance of the spring I8, reduction in speed of the shaft 9 causing a reversal of movement of the sleeve l6;

proper comprises a plurality of contact segments l9, Isa, [9b,

a shaft 26a constituting anextension of bolt '22 parts controlled thereby. v

It will be seen that as the shaft 9 rotates, the sleeve IE will reciprocate longitudinally on said shaft, thereby actuating the crank or lever 26 and causing the brush 25a to wipe the contact segments |9a-|9f in successive order ,and in accordance with the adJustment of the latter.

the brush, for the remaining segments.

A resistance unit or rheostat 28 is shown mounted in an insulating block 280:. secured to the inner side wall of the casing 8. Another brush or contact spring 29 is connected to the block 25 opposite the brush 25a and is energized through contact with the latter. A wire 30, note Fig. 5, connects with could be substituted by or the like.

As will be obvious, the contact segments may be varied in number in accordance with the number of signals to be accommodated.

The switch operates as follows, reference being made to the wiring diagram in Fig. 5 in conjunction with the remaining figures:

It will be noted that the Battery B is connected directly to the common conductor maintenance of accuracy throughout long pe- Alsoyspring tolerances or, variations may be readily compensated for.

Another feature to which attention is directed is the absolute lack of arcing between the brush or main contact member 25a and the contact plates l9-l9f and which is always present to some extent at least in switches where the contact members are of direct make and break type, or where they contact over their full area substantially simultaneously and break in the same manner. Such arcing results in burning which soon deteriorates the contacts and tends towards sticking and inaccuracy in signal response.

It will be observed from Figs. 4 and 5 that the brush 25a constitutes in effect a plurality of contact members which are resilient and independently movable or flexible relative to one another, so that when the brush is actuated bodily to move these contact members into engagement with the surfaces of the stepped contacts I9l9f, the contact members flex and successively engage the contacts until the switch arm moves in the reverse direction whereupon they successively disengage the said contact surfaces.

Means are provided for mechanically connecting the governor shaft 9 with the drive shaft of a speedometer, note Fig. 2.

It will be understood that certain changes in structure and design of the improved unit may be adapted generally within the scope of the invention as defined by the appended claims.

We claim:

1. In a switch unit of the type specified, a governor, a plurality of plate-like contact members having edge contact surfaces arranged in stepped relation arcuately, a switch member having a brush adapted to wipe said contact surfaces, said switch member having an operative connection with said governor to be actuated thereby, and means for relatively arcuately adjusting the individual contact members for a definite speed response.

2. In a switch unit of the type specified, in combination, a governor, a switch arm operatively connected to said governor to be actuated thereby, a bank of substantially flat contact segments clamped together fiatwise and having insulation material therebetween, the contact edge portions of said segments being arranged in stepped relation arcuately, one of said segments constituting a common conductor segment and having its arcuate contact edge contoured to follow the line of contact of the remaining group of segments, and means electrically connecting said common conductor segment to a source of electrical energy.

3. In a switch unit of the type specified, a bank of substantially flat contact segments having insulation or dielectric material therebetween, the contact edges of said segments being arranged in stepped relation arcuately, and means adjustably clamping said segments in bank formation, the switch being adjusted by loosening the bank and arcuately moving said segments.

4. In a switch unit of the type specified, a governor, a switch arm operatively connected to said governor to be actuated thereby, a contact brush carried by said .switch arm, a plurality of flat contact segments with insulation or dielectric material therebetween, the contact edges of said segments being arranged in stepped relation arcuately with one of said segment-s having its arcuate contact edge shaped to follow the arcuate contour of the entire group of segments, and means adjustably clamping said segments in bank formation.

5. A governor-controlled switch unit comprising a governor, an arcuately movable arm connected to said governor to be actuated thereby, a bank of contact segments arranged flatwise with insulation material therebetween, said segments having their contact edge portions contoured arcuately with one of said segments constituting a common conductor segment and having a contact edge describing an are substantially equal to that defined by the contact edges of the remaining segments, and a contact brush mounted on said arm and adapted to wipe said contact edges, said brush spanning the entire width of the bank.

6. In combination, a governor-controlled switch including a spring adapted to be compressed due to centrifugal action of the governor, a switch arm operatively connected to said governor to be actuated thereby, a bank of contacts stationarily mounted with respect to said switch arm, a brush mounted on such switch arm and adapted to wipe said contacts in successive order, and means for relatively adjusting the individual contacts for a definite speed response and also to compensate for spring tolerances.

'7. In a governor controlled switch, a switch arm operatively connected to the governor to be actuated thereby, a bank of individual contacts stationarily mounted with respect to said switch arm and having contact surfaces arranged in progressively stepped relation, contact members actuated by said arm to engage said contact surfaces in successive order, said contact members being resilient and independently movable relative to one another whereby when they are moved into engagement with said contact surfaces during movement of the switch arm in one direction they flex and successively engage the said surfaces and remain in contact therewith until the switch arm moves in the reverse direction. whereupon they successively disengage the said contact surfaces, and means for adjusting said individual contacts with respect to one another for definite speed responses.

8. In a governor controlled switch including a spring adapted to be compressed due to centrifugal action of the governor, a switch arm operatively connected to the governor to be actuated thereby, a bank of individual contacts station- 'arily mounted with respect to said switch arm and having contact surfaces arranged in progressively stepped relation, resilient independently flexible contact members movable by said switch arm into successive engagement with said surfaces, and means for adjusting said individual contacts with respect to one another and also with respect to said flexible contact members for definite speed responses and also to compensate for spring tolerances.

9. In combination a governor controlled switch including a governor shaft carrying centrifugal weights and a spring mounted on said shaft and adapted to be compressed due to the action of said weights, a switch arm operatively connected to said governor to be actuated thereby, a bank of individual contacts stationarily mounted with respect to said switch arm and having progressively stepped contact surfaces, resilient independently flexible contact members movable by said switch arm into successive contact with said surfaces, and means for adjusting said individual contacts with respect toone another and also with respect to said flexible contact members for definite speed responses and also to compensate for governor spring tolerances.

10. A governor-controlled switch unit including a plurality of plate-like contacts clamped together with di-electric material therebetween and having edge contact surfaces arranged in stepped ,relation arcuately, a switch arm operatively connected to the governor to be actuated thereby, a brush connected to said arm and arranged to engage the edges of said contact members in successive order, the edge con-tact surfaces of said contact members being formed with radially projected stepped surfaces for continuous contact with said brush once contact is established, and means for relatively adjusting said contacts.

ELMER G. STRECKFUSS. GILES S. MOORE. 

